1. Field of the Invention
The present invention relates to an airway for sole esophageal obturator or endotracheal and esophageal-obturator ventilation. The airway of the present invention particularly relates to an airway that is used in an emergency situation and whose position and orientation can subsequently be accurately determined by X-ray, ultrasonographic or fluoroscopic examination.
2. Description of the Related Art
Airways have been developed for use in emergency resuscitation so that the insertion of the airway by first-aid personnel can be performed. For instance, a single-lumen airway for insertion into the esophagus that is sealed to the external environment by a face mask is known, e.g., by Don Michael T. A., Lambert E. H., Mehran A.; Lancet p. 1329, 1968. During ventilation air is guided from the lumen of the airway through the air-outlets to the patient. However, the sealing of the airway against the surrounding air is problematic as one has to press the face mask to the face of the patient to obtain adequate an effective seal thereby usually demanding an assistant.
A twin-lumen airway is described in AT-PS No. 376,128. This airway can be inserted into the trachea or into the esophagus by choice. In the first case, the air passes from the one lumen directly into the trachea, while in the second case the air passes from the other lumen through the air outlets. Also with this airway a face mask is recommended.
According to DE-OS No. 21 20 164, an airway is provided which shows two parallel tubes. One tube is inserted into the esophagus and may be sealed by a cuff. This tube does not conduct air but is used to withdraw gastric fluid by suction. Ventilation is carried out through the second tube which ends in the cavum pharynges. For sealing purposes, a further cuff may be provided replacing a mask by sealing the cavum pharynges directly. However this airway must not be inserted into the trachea or esophagus by choice. If this airway is inserted into the trachea, ventilation is impossible.
Other emergency airways are described in U.S. Pat. Nos. 4,231,365, 4,334,534 and 4,688,568. In U.S. Pat. No. 4,231,365, there is illustrated an emergency resuscitation apparatus including an endotracheal tube having a tracheal obturator and a second expandable cuff for sealing against the pharyngeal tissues to provide an alternate sealing for respiratory fluids if the blind intubation is not successful. A laryngeal tube passes through the pharyngeal obturator for alternatively introducing respiratory fluids into the lungs through the larynx. The endotracheal tube may also be used as an esophageal obturator and inserted without the intubating guide means. To support the tubes and ensure intubation to the correct depth, a face shield is provided.
U.S. Pat. No. 4,334,534 describes an emergency airway tube for use in resuscitation of non-breathing patients by inserting the tube through the mouth until it randomly lodges either in the trachea or the esophagus. The tube has an outer tube, an inner tube which runs along and within the bore of the outer tube, and an air passageway for inflating an inflatable cuff located at the distal end of the outer tube which enters the trachea or esophagus. The end of the inner tube has a pneumatic seal for forming an airtight fit within an adjacent distal end of the outer tube. The outer tube has a cluster of side air ports in its wall located generally midway between the ends of the tube. If the tip of the tube engages the trachea on insertion, the cuff is inflated and the inner tube will be the air passageway to ventilate the patient. If the tip of the tube engages the esophagus, the cuff will seal off the stomach. The outer tube will be the air passageway to ventilate the lungs by way of the side air ports in the outer tube wall. A face mask is placed over the face of the patient to stop air leakage while the patient is being ventilated via the air ports.
U.S. Pat. No. 4,688,568 discloses an airway for sole esophageal obturator or endotracheal and esophageal-obturator ventilation by choice. The airway has an inflatable distal cuff and air outlets in its wall in the area of the pharynx. The airway also has an inflatable pharyngeal cuff that surrounds the wall of the airway above the air outlets in that area and which, when the airway is inserted, is situated between the soft palate and the boundary between the base of the tongue and the back of the tongue.
Although known emergency airways have been used to successfully resuscitate patients, a problem can arise when the patient is further treated by personnel different from those who originally inserted the airway. In particular, it is sometimes difficult to determine the precise position and orientation of the airway within the patient which may be crucial before the patient can be further treated. Furthermore, it is undesirable to remove and reposition the airway or to use a new airway in view of time and possible additional danger to the patient, particularly in instances of spinal or facial trauma.
While the art has described an X-ray marking line in conventional endotracheal tubes, such as in U.S. Pat. No. 4,150,676, there is still a need for an efficient and effective way to determine the precise location of a double lumen airway.